The present invention relates to a neighboring picture operation unit for carrying out arithmetic processing with respect to picture elements adjacent to each other.
Specifically, this invention relates to a calculating device for calculating the position of the maximum intensity pixel in the neighboring pixels, and for determining the relationship between the position and intensity of the pixels of the image, such as the order of the intensity or the like. Accordingly, the data thus obtained is a (X, Y) coordinate representing the position and the intensity (light and shade) of the image such as an intensity distribution or the like.
The neighboring picture element (neighboring pixel) is defined by the pixel which exists in the neighborhood of a noticed pixel in the center as shown in FIG. 1 attached to this letter. The selection of the neighboring pixel is varied with application fields. For example, frequently the neighboring pixels are selected from the immediate neighborhood of the noticed pixel as shown in FIG. 2.
The noticed pixel is arbitrarily selected, and therefore all of the pixels of an image have their neighboring pixels. Using arbitrarily selected noticed pixels and the respective neighboring pixels thereof, for example, this invention can determine a distribution in light and shade of an image such as a streak image or the like.
Conventionally, in a neighboring picture operation unit for a picture presented with light and shade, the system carrys out operations on intensity information on the light and shade in the vicinity of the picture.
This processing of picture elements is carried out by a combination of binomial operations on intensity information for those picture elements as illustrated by FIG. 2. Binominal operations include both Boolean operations such as AND, OR, COMPARE or the like and arithmetic operations such as ADD, SUB or the like. The shade information on the light and shade of each picture element is represented by a binary code. In this case, it is defined that the higher the bit position of the bit having a "1" the higher the intensity of a picture element. FIG. 2 shows an example of a circuit for carrying out processing for eight picture elements by a combination of binomial operations an intensity information of the picture elements. The shade of each picture element is represented by digital code (binary code). The binary code representing the intensity of each picture element (1-8) is inputted to one of input terminals of each comparator, and compared with the other binary code of adjacent picture element inputted to the same comparator to thereby output the binary code having a "1" in the highest bit position thereof. At the same time, the position of the picture element of the binary code having "1" in the higher figure in each comparator is detected or memorized by position detecting means (not shown). At the next stage, a pair of the binary codes outputted from the compartor and the adjacent comparator thereto are inputted to another comparator and compared with each other, thereby to output the binary code having "1" in the higher bit position thereof and detect the position of the picture element. The above operation is repeated a number of times to determine the picture element binary code having "1" in the highest bit position thereof and detect its position.
In this system, however, if information as to the relation of intensity information among a group of neighboring picture elements is to be obtained, it is necessary to change the processing procedure in various manners. For example, there are disadvantages in using one and the same operation to obtain information on the position of a picture element having the largest intensity among numbers of input picture elements, the position of a picture element having the smallest intensity, the position of a picture element having the intermediate intensity, the position of a picture element of a having a desired intensity and so on.